Introduction

Spirometry requires maximum patient effort in order to achieve acceptable and
repeatable results. Coaching patients on the correct technique and providing
feedback can improve the quality of spirometry data. This is provided by trained
medical staff in the clinic and is centred on the ATS/ERS 2005 criteria1 on
acceptability and repeatability, which is widely used in clinical trials to determine the
quality of spirometry results. At home, sophisticated spirometers are needed to
provide feedback to the patient on test performance and repeatability, in order to
obtain good quality data in the absence of a trained coach.

In respiratory clinical trials, home measurements of lung function (including PEF and
FEV1) are of particular importance, since they are frequently used as endpoints for
efficacy and safety. Thus, the ability of patients to provide high quality data is crucial.

Electronic Spirometry e-Diaries are often used in clinical trials to record home
measurements. In a previous clinical trial where 113,098 Home Pulmonary Function
Tests (PFTs), sessions were recorded using the previous model of the Vitalograph
e-Diary, where limited feedback was given to the patient on test quality. 85% of the
PEF measurements and only 63% of the FEV1 measurements met the ATS/ERS 2005
repeatability criteria2,3.

The new Vitalograph In2itive e-diary provides even more accurate feedback
regarding patient technique and repeatability; this has the potential to improve the
quality of home spirometry data.

Aim

To determine the repeatability of home PEF and FEV1 data collected using the
Vitalograph In2itive e-Diary in an international multi-centre, double blind, placebo-controlled
clinical trial with adolescent and adult patients with asthma.

Method

During this study 174 patients were each provided with a Vitalograph In2itive
e-Diary at the screening visit andwere instructed by the trained site staff to use the
e-Diary twice a day to record asthma symptoms and PFTs,first in the morning
between 6am-11am and then again in the evening between 6pm-11pm. The data
collectedon the e-Diary in the morning and evening were treated as separate
sessions.

Clinic Visits

The total duration for patients that completed the trial was 14-20 weeks. For those
patients who were notrandomised, maximum total duration for the screening and
run-in period was up to 8 weeks.

Training and Feedback

At the screening visit, patients were trained
on how to use the e-Diary and perform a
correct PFTmanoeuvre by the site staff.

The e-Diary also provided instructions to the
patient on how to perform their PFT correctly.

Once the PFT manoeuvre was completed the
e-Diary provided feedback on the quality of
the test.

If the patient was able to achieve 3 good tests that met
the ATS/ERS 2005 criteria1 for repeatability the e-Diary
would indicate the session has been completed.

If the patient did not meet the ATS/ERS 2005 criteria1 for
repeatability, the e-Diary would provide feedback that
theblows were not consistent and ask the patient to
perform another test. The e-Diary allowed a maximum
of 5 PFT teststo be performed by the patient per
session.

Home PFT sessions from 174 patients who participated
in the clinical trial from 09-Nov-2011 to 18-Dec-2012
wereused in this analysis.

Results

A total of 35,615 Home PFT sessions were recorded using the In2itive e-Diary
device. 17,886 AM and 17,729 PMsessions were recorded. The repeatability for
both PEF and FEV1 was calculated as the difference between the twohighest
readings (Table 2).

95.2% of the sessions achieved the ATS/ERS 2005 repeatability criteria1 for PEF.

96.7% of the sessions achieved the ATS/ERS 2005 repeatability criteria1 for FEV1.

96% of the sessions had 3 or more PEF results, however this dropped to 94% for FEV1 (see table 3). There were48 (0.13%) sessions that had no PEF data recorded,
and 645 (1.81%) sessions where no FEV1 data was recorded.597 of these sessions did have PEF measurements, so despite the feedback message to the patient to
‘blow longer’this didn’t result in an expiration time of at least 1 second.

Table 2: % of accepted and rejected sessions as judged by repeatability

Conclusion

Using the new Vitalograph In2itive e-Diary, asthmatic patients in this clinical trial were able to produce more repeatable PEF and FEV1 results at home compared to
previous trials that have used the older design of the e-Diary. Providing instant feedback to the patient the In2itive e-Diary has been shown to improve the quality
of the spirometry that patients can achieve when performing PFTs at home, in both PEF and FEV1.

This instant feedback is important for patients when recording PEF and FEV1 at home in the absence of coaching and guidance from trained medical staff which is
only present during clinic PFTs. In this clinical trial, the number of FEV1 manoeuvres recorded using the new In2itive e-Diary increased dramatically compared to the
older design of the e-Diary which provided less feedback. When using the new Vitalograph In2itivie e-diary in clinical trials improved collection of home
spirometry data can be expected with greater accuracy and repeatability.